I reviewed the report the inspector gave saying the system TD was out of tolerance. I new there was an issue as soon as I saw the picture of inspector using temp gun. *******These measurements are not accurate ********** Using temperature probs at the unit from return and supply are the only way to get an accurate reading of true TD specs. I tested both system is heat and cooling. Readings Upstairs -TD in heating 132 supply return 84 Upstairs - TD in cooling 66 return supply 45 Down stairs TD heating 142 supply return 84 Down stairs TD cooling 66 return supply 45 Cooling TD for down stairs system is question is 23° System test in tolerance all the way around.